Add hijack_dns for tun

dns/transport.go

@@ -20,6 +20,9 @@ func NewTransport(ctx context.Context, dialer N.Dialer, logger log.Logger, addre
 		return nil, err
 	}
 	host := serverURL.Hostname()
+	if host == "" {
+		host = address
+	}
 	port := serverURL.Port()
 	switch serverURL.Scheme {
 	case "tls":

dns/transport_tcp.go

@@ -87,7 +87,7 @@ func (t *TCPTransport) newConnection(conn *dnsConnection) {
 		}
 	})
 	conn.err = err
-	if err != nil {
+	if err != nil && !E.IsClosed(err) {
 		t.logger.Debug("connection closed: ", err)
 	}
 }

dns/transport_tls.go

@@ -95,7 +95,7 @@ func (t *TLSTransport) newConnection(conn *dnsConnection) {
 		}
 	})
 	conn.err = err
-	if err != nil {
+	if err != nil && !E.IsClosed(err) {
 		t.logger.Debug("connection closed: ", err)
 	}
 }

dns/transport_udp.go

@@ -8,6 +8,7 @@ import (
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
 	M "github.com/sagernet/sing/common/metadata"
 	N "github.com/sagernet/sing/common/network"
 	"github.com/sagernet/sing/common/task"
@@ -83,7 +84,7 @@ func (t *UDPTransport) newConnection(conn *dnsConnection) {
 		}
 	})
 	conn.err = err
-	if err != nil {
+	if err != nil && !E.IsClosed(err) {
 		t.logger.Debug("connection closed: ", err)
 	}
 }